Clip stack

ABSTRACT

A clip stack, a method of forming a rigidified joint, and the resulting joint. Filler material is positioned adjacent wires to be clinched by a clip, and is clinched with the wires to deform and to be compressed by the clip and wires to form a stronger and more rigid joint. The filler material may be carried by the clip, and may be severed from a clip stack joined by a strand of filler material from which filler material is severed as a clip is separated from the stack. The filler material may be at both sides of the stack and in an interference fit in notches in opposite sides of the clips of the stack.

United States P310111 Plunkett 51 Mar. 27, 1973 CLIP STACK [75]Inventor: Larry D. Plunkett, Crystal Lake, Ill. [73] Assignee: SignodeCorporation, Glenview, ill. [22] Filed: Mar. 19, 1971 [21] Appl.'No.:126,018

UNITED STATES PATENTS 12/1965 Couch ..206/56 DF 3,363,628 1/1968 Woodt....'.206/56 DF UX 1,026,050 '5/l9l 2 Reber .;206/56 DF 2,746,601 5/1956Rebichon ..206/65 K 10/1971 Langas et al. ..206/56 AC 9/1954 Chaffee..206/56 AC [57] ABSTRACT A clip stack, a method of forming a rigidifiedjoint, and the resulting joint. Filler material is positioned adjacentwires to be clinched by a clip, and is clinched with the wires to deformand to be compressed by the clip and wires to form a stronger and morerigid joint. The filler material may be carried by the clip, and may besevered from a clip stack joined by a strand of filler material fromwhich filler material is severed as a clip is separated from the stack.The filler material may be at both sides of the stack and in aninterference fit in notches in opposite sides of the clips of the stack.

7 Claims, 10 Drawing Figures our STACK This invention relates to amethod of forming a rigidificd joint consisting of at least a pair ofelements, such as wires locally embraced by a clinched clip, to theimproved joint so formed and to a clip stack especially assembled to beused in forming such a rigiditied joint. 1

It is well known in the art to join elongate elements, such as wiresforming automobile seat springs and the like, to each other to form aspring assembly or the like..-

A commonly used expedient for joining such elements locally is a clip,which clip is then clinched about the elements. A typical clip and atypical tool for clinching such a clip are illustrated in US. Pat. No.2,574,811. Other clips used for similar purposes are illustrated, forexample, in US. Pat. No. 3,032,184.

Although clips of the types illustrated in such patents have been usedsuccessfully to locally join elements, such as wires, too frequently thejoints formed are somewhat loose, sometimes resulting in misalignment ofparts of the joined elements, sometimes resulting in squeaky assemblies,etc. Furthermore, clips of the types illustrated in such patents, to beusable in fastacting tools must be assembled into stacks. Althoughvarious modes of assembling them have been suggested and used, moststacks require either difficult assembly operations to form them or onceformed are too rigid or fragile, which stacks then easily separate andscatter, unless very carefully handled.

In accordance with this invention, an improved clip stack is provided,which clip stack when used in a clinching tool results in the formationof an improved localized joint.

Joints formed in accordance with prior art procedures usually comprise aclinched clip and at least a pair of elongate elements, such as wires,locally embraced by the clinched clip. An improved joint of this 7invention also incorporates tightly compressed dunnage or fillermaterial disposed between the clinched clip and the wires, and inengagement with each of them, for resisting movement of the wires withrespect to the clip. Theclip may also be notched to provide a localizedweak area, so that as it is clinched about the wires, it buckles intocloser conformity with the wires, thereby further to assist in providinga rigidified joint.

To form such joints, a clip and filler material are positioned adjacentthe localized region of the wires to be clinched, and the clip isclinched about the wires and the tiller material, to compress, to deformand to relocate the filler material, thereby to form a tightly wrappedjoint.

In a preferred embodiment, the filler material is associated with theclip as it is separated from a clipstack, and is carried by the clipinto engagement with the wires, where the filler material is released tobe compressed and deformed within the clinched clip to form therigiditied joint. When the filler material is associated with the clip,it preferably derives from continuous filamentary key material joining aplurality of like clips into a stack. In such a stack, the clips may begenerally U-shaped and define notch segments longitudinally of the stackfrictionally engaging the key material, so that when a clip isseparatedfrom. the

stack, a segment of the key is severed from the key material and thatsegment is then carried by the clip for subsequent compression anddeformation in the joint.

Further objects, features and advantages of this invention will becomeapparent from the following description and drawings of which:

FIG. 1 is a perspective view of a clip formed in accordance with thepresent invention;

FIG. 2 is a perspective view of a clip blank from which the clip of FIG.1 may be formed;

FIG. 3 is a perspective view of a stack of clips in'accordance with FIG.1;

FIG. 4 is an enlarged fragmentary view of a portion of a clip of thestack of FIG. 3;

FIG. 5 is a fragmentary view of a clip tool, prior to separation of aclip from a clip stack; 7

FIG. 6 is a view similar to FIG. 5, showing a clip separated from theclip stack;

FIG. 7 is a view similar to FIG. 5, showing a partially clinched clip;

FIG. 8 is an enlarged view similar to FIG. 7, showing the clip of FIG. 7fully clinched;

FIG. 9 is a perspective view of a clinched clip and joint of FIG. 8taken substantially along the line 99 of FIG. 10; and

FIG. l0-is a fragmentary perspective view of a spring assembly clinchedin accordance with this invention.

The clips cor the embodiment of FIGS. 1 to 4 are each formed from arectangular sheet metal blank B (FIG. 1) that includes openings in theform of slots or notches in opposite side edges thereof. Preferably theblank B comprises notch means including a first pair of notch segmentsor notchesl2 and a second pair of notch segments or notches 14, eachpair at one side edge -10 of the blank. Preferably the notches 12, 14are formed by a punching operation. The'blank B is bent around agenerally centrally disposed fold line 16 to provide a generally roundedcentral body portion 18, and downwardly extending, spaced parallel legportions 20.

Theresulting clips C are adapted to be positioned in an adjacent orjuxtaposed relationship with respect to one another, with the surfacesof the leg portions 20 of adjacent clips to be positioned in abuttingcontact with each other, thereby to be formed into stacks S in themanner to be described.

When the clips C are so positioned, as is illustrated in FIG. 3, thenotches 12, 14, respectively, are aligned longitudinally of a stack. Inthat condition, notches 12, 14 are adapted, respectively, to receivecontinuous connecting filamentary keys or filaments 22 at opposite sideedges 10, desirably in an interference fit.

Typical suitable filaments 22 are illustrated as being generallycircular in cross-section and as having a diameter slightly greater thanthe width of notches 12, 14. (See FIG. 4.) As such, when the filaments22 are press fit into frictional engagement in notches l2, 14, theyfunction as keys to secure the clips C to each other in continuousstacks S. Desirably, the transverse dimension of the notches 12, 14 is,greater than the vertical dimension, so that when the filamentarymaterial is circular, it is completely within the confines or projectionof the side edges 10 of the stack S. Regardless of the configuration ofthe filament 22, it is desirable that itbe entirely within the confinesof the side edges 10, so

that when a joint is formed, as'will be described, the' filamentarymaterial is retained in the joint. Illustratively, notches 12, 14 may beabout 0.062 inch wide and about 0.12 inch deep. The filaments 22 may beabout 0.067 inch in diameter.

. 3 Filaments 22are preferably formed of an inexpensive plasticmaterial, such as a low-density polyethylene, Such filaments aresufficiently limber to allow the individual clips in the stack S to flexslightly.

relative to. one another, and are sufficiently soft to .stack to beinserted into a curved chute, which could even be coiled to provide anextremely compact clip dispensing unit. In use, the individual clips ofsuch a to a position in which the ends of the leg portions contact theclinching surfaces of the jaw 50, gradually to wrap the clip about thelocalized region of th'e'wires W, i.e., for example, as progressivelyillustrated in,

FIGS. 6 to 8.

As the segments 22' are compressed against and between the inner surfaceof clip C and the wires W they gradually deform and are extruded. l'nthe case of polyethylene, they may well be shorn or cut into severalrelocated sections 22", but, many event, the material remainssubstantially within the confines of the side edges 10 of the clinchedclip C, thereby to provide stabilizing and rigidifying filler betweenthe wires and the 7 clip C'. The filler material may tend to be extrudedstack S can be readily separated from one another,

- since bymoving one clip transversely relative to the stack with even arelatively small force will cause shearing and severing of the filaments22.

Although polyethylene is a preferred material, for the purpose ofproviding a filler material to enhance joint rigidity, other materialsmaybe used as well, such as, forexample, soft wire, twine, solder, etc.

The clips Cof FIGS. 1 to 4 are adapted to be used to clinch at least twoelongate elements, such as wires or the like together, to form arigiditied localized joint" 52. A stack S of clips maybe fed to theposition illustrated in FIG. 5 in a magazine 54 associated with thetool, as by a suitable follower (not shown). vA typical clinching tool40 embodying such features is described 7 in Blume'nsaadtUS. Pat. No.2,574,811.

' A clip stackIS, as'illustrated in FIG. 3, is placed injoint stability.

magazine 54 in known manner and is fed or biased into the positionillustrated in FIG. SiWhen the tool is to be used, at least a pair ofelongate wires W are positioned adjacent the jaw 50, with the localizedregionsto be clinched, being positioned within the side edges of thejaw. Wires W may be circular in cross section, or may be of othercross-sectional configurations/With the wires W so positioned, the toolis actuated and the clinching-blade 52 is thrust downwardlyfrom theposition of FIG, 5 towards the jaw 50. It contacts a central bodyportion 18 0f a clip C, and drives the clip C downwardly simultaneouslysevering a clip C and shearing filament segments 22' from the stack 8adjacent the interface of adjacent leg portions 20.

Because the segments 22 are supported in the spaced apart notch segments12, 14, respectively, the severed clip C carries segments 22 downwardly,-as illustrated in FIGS. 3 and 6. The clinching blade 52 then releasethe segments 22 from the notches 12, 14, and

laterally of the clip, in addition to being relocated vertically (asillustrated in FIGS. 8 and 9). As such, the filamentary materialcooperates to form a rigiditied joint which resists relative movementbetweenthe clinched .clip C and the wires W, both longitudinally of thejoint 100, and about the axes of the wires W. The spaced pair oflaterally spaced segments 22' form relocated sections 22" at two spacedareas, further enhancing The upper surface of a wire W will cooperatewith. the inner surface of the clip in the manner of a hammer and anvilto deform, ex'trude and relocate the filler material. When the wires Ware circular in cross section, the wire and clip surfaces will tend torelocate the filler material into the areas adjacent the contactingsurfacesof the wires, and only a very small amount of tiller materialwill be necessary to stabilize the joint, as

at the 'two localized areas in the embodimentillustrated. v

' As best seen in Fig. 8, the joint 100., at its sides,

defines slightly convex or buckled sections 102 confronting thecontacting" surfaces of wires W. That results from thetendency of' theclip C to buckle preferentially generally along an imaginary linebetween spaced'opposite notches 12, 14 in a leg 20. That preferentialbuckling also contributes to a tighter, more rigid joint than thoseobtained with conventionalclips which have no notches 12, 14, such asthose "illustrated in the aforementioned Blumensaadt patent.-

tioned, they may also take the form of other material,

such as an adhesive, or solder or the like, which, when suitablyactivated, asby heat, will physically secure the elements of the joint-100 to each other. Further, it will 1 'be apparent that clips of othershapes; and with notches in other positions may be used to form clipstacks joined by filaments in notches therein to form a joint inaccordance with this invention. Exemplary of other 'such clips are thoseillustrated in US. Pat. No.

3,032,184. And, it will be clear, that in forming a rigiditied joint,filler material may be introduced separately from the clip, as with thewires, to position it for clinching with a clip and wires to form afilled, rigidified joint.

While this invention is susceptible of embodiment in many differentforms, there has been shown and described in detail preferredembodiments of the invention, with the understanding that the presentdisclosure is to be considered as an exemplification of the principlesof the invention and is not intended to limit the invention to theembodiment illustrated. The scope of the invention will be pointed outin the appended claims.

What is claimed is:

1. An elongate clip stack comprising a plurality of similarly shaped,non-nested adjacent clips, each clip being generally U-shaped incross-section, and each clip including spaced, generally parallel, legportions extending downwardly from a central web portion, each clip insaid stack being positioned with its leg portions in contact with legportions of next adjacent clips, each said clip defining notch meansaligned with notch means of other of said clips longitudinally of saidstack, each leg portion having outer edges with an outwardly facingnotch segment in an outer edge of each leg portion, the notch segmentsof each clip cooperating to form a said notch means, all of said notchmeans collectively defining a keyway extending longitudinally andopening outwardly of said stack, a filamentary key in frictionalengagement within each of said spaced notch segments, whereby when aclip is separated from said stack, a segment of said filamentary keybetween said notch segments is severed from the key and is carried by asaid separated clip.

2. An elongate clip stack in accordance with claim 1-, wherein saidfilamentary key is positioned in said notch segments completely withinthe' confines of said outer edges.

3. An elongate clip stack in accordance with claim 1, comprising secondnotch segments in opposite outer edges of said leg portions, wherebyopposed notch segments define a weakened zone to facilitate buckling ofthe clip when clinched to embrace wires.

4. An elongate clip stack in accordance with claim 1, comprising secondnotch segments and a second filamentary key in opposite side edges ofsaid leg portions, whereby when a clip is separated from said stack,segments of said filamentary keys between said notch segments aresevered from said keys and are carried by a separated clip.

5. An elongate clip stack in accordance with claim 1 wherein saidfilamentary key is generally circular in cross-section, and slightlylarger in diameter than the width of each notch segment.

6. An elongate clip stack in accordance with claim 5, wherein saidfilamentary key is formed of a limber plastic material.

7. An elongate clip stack in accordance with claim 6, wherein saidfilamentary key is formed of a low-density polyethylene.

1. An elongate clip stack comprising a plurality of similarly shaped,non-nested adjacent clips, each clip being generally Ushaped incross-section, and each clip including spaced, generally parallel, legportions extending downwardly from a central web portion, each clip insaid stack being positioned with its leg portions in contact with legportions of next adjacent clips, each said clip defining notch meansaligned with notch means of other of said clips longitudinally of saidstAck, each leg portion having outer edges with an outwardly facingnotch segment in an outer edge of each leg portion, the notch segmentsof each clip cooperating to form a said notch means, all of said notchmeans collectively defining a keyway extending longitudinally andopening outwardly of said stack, a filamentary key in frictionalengagement within each of said spaced notch segments, whereby when aclip is separated from said stack, a segment of said filamentary keybetween said notch segments is severed from the key and is carried by asaid separated clip.
 2. An elongate clip stack in accordance with claim1, wherein said filamentary key is positioned in said notch segmentscompletely within the confines of said outer edges.
 3. An elongate clipstack in accordance with claim 1, comprising second notch segments inopposite outer edges of said leg portions, whereby opposed notchsegments define a weakened zone to facilitate buckling of the clip whenclinched to embrace wires.
 4. An elongate clip stack in accordance withclaim 1, comprising second notch segments and a second filamentary keyin opposite side edges of said leg portions, whereby when a clip isseparated from said stack, segments of said filamentary keys betweensaid notch segments are severed from said keys and are carried by aseparated clip.
 5. An elongate clip stack in accordance with claim 1wherein said filamentary key is generally circular in cross-section, andslightly larger in diameter than the width of each notch segment.
 6. Anelongate clip stack in accordance with claim 5, wherein said filamentarykey is formed of a limber plastic material.
 7. An elongate clip stack inaccordance with claim 6, wherein said filamentary key is formed of alow-density polyethylene.